When are we getting rid of 100LL?

[AlphaPilotFlyer]

Besides the environmental hazard of leaded gas, and higher cost, I think the biggest concern we GA guys should have is the imminent outlawing of it. California has filed multiple lawsuits against distributors but were essentially dismissed due to federal govt arguing in the distributors favor as there is currently no substitute and would shut down GA. California stated they will outlaw it in the state as soon as ANY substitute is available regardless of price. Other states followed with similar intentions. Most expect all states will follow so as not to be the only state polluting the air with lead.

So, it’s reasonable to believe AVGAS will not likely be available as soon as FAA signs off on alternative. And if it is still available, the lower volume of production would be so small it’s cost would likely sky rocket. Already there is only a single producer of TEL (lead additive) that continues facing pressure for producing it.... if they stop, there’s not likely anyone else that would start up to replace.

the FAA has been shopping for AVGAS substitute for decades. When they do find a supplier, they will have a monopoly and a captive audience. I remember when synthetic motor oil first appeared, it was almost 3X cost of conventional oil. This may be the case with any new AVGAS initially. Electric is the future, but not anytime soon for most GA budgets and mission.

I’ve read some owners experience premature engine wear and problems they claimed were a direct result of burning non ethanol MOGAS under a STC. Not sure what was ever proved, but most owners I know don’t want to chance it, and say it’s harder to find. I have a c172 with a flex fuel rated engine so can use multiple fuel types and mostly burn low octane car gas with ethanol, mostly cause it’s cheap. The FBO on the field sells it to support field vehicles and ground equipment, so it’s cheap and easy to get for me. But normally we just fill up two 5 gallon cans at gas station a block away to save about 50cents/gal.... also can get up-to 30 cents/gal tax back for non highway use... so typically pay about $2/gal whereas local AVGAS is about $4.80/ gal. Same station also has non-ethanol REC 90 gas which I use when the plane is not going to fly much as it has longer storage time in plane, it it cost about 40 cents /gal more and engine runs same.

A buddy asked me to recommend a first airplane to buy after getting his private, and said I’d find one that has the MOGAS STC available for above reasons.

does anyone have history with using the MOGAS non-ethanol fuel STC? How difficult is it to find on a typical GA field?

 

[3393RP]

Sorry. It is a rather long article. I don't want to paste the whole thing. Suffice to say, it was a front page article on the Orlando Sentinel with a big picture above the fold and fairly large type headline. And we are going to be hearing about this more and more in the coming months and years.

You can bet on that.

 

[EdFred]

What is the biggest threat from using zero percent ethanol MOGAS in certified legacy engines? Vapor lock?

Yes, although it's not necessarily the engine, but the routing of the fuel to the engine. The O-540 can run it certain airframes, but on other airframes vapor lock happens. Even the O-300 will vapor lock when it's 90+ degrees out. Direct injection would/could/should(?) solve the issue, but that's not exactly a legacy engine, and good luck on getting the FAA to allow Lycontinental to build them cheaply to retrofit a couple hundred thousand airframes.

 

[Cap'n Jack]

Besides the environmental hazard of leaded gas, and higher cost, I think the biggest concern we GA guys should have is the imminent outlawing of it. California has filed multiple lawsuits against distributors but were essentially dismissed due to federal govt arguing in the distributors favor as there is currently no substitute and would shut down GA. California stated they will outlaw it in the state as soon as ANY substitute is available regardless of price. Other states followed with similar intentions. Most expect all states will follow so as not to be the only state polluting the air with lead.

So, it’s reasonable to believe AVGAS will not likely be available as soon as FAA signs off on alternative. And if it is still available, the lower volume of production would be so small it’s cost would likely sky rocket. Already there is only a single producer of TEL (lead additive) that continues facing pressure for producing it.... if they stop, there’s not likely anyone else that would start up to replace.

the FAA has been shopping for AVGAS substitute for decades. When they do find a supplier, they will have a monopoly and a captive audience. I remember when synthetic motor oil first appeared, it was almost 3X cost of conventional oil. This may be the case with any new AVGAS initially. Electric is the future, but not anytime soon for most GA budgets and mission.

I’ve read some owners experience premature engine wear and problems they claimed were a direct result of burning non ethanol MOGAS under a STC. Not sure what was ever proved, but most owners I know don’t want to chance it, and say it’s harder to find. I have a c172 with a flex fuel rated engine so can use multiple fuel types and mostly burn low octane car gas with ethanol, mostly cause it’s cheap. The FBO on the field sells it to support field vehicles and ground equipment, so it’s cheap and easy to get for me. But normally we just fill up two 5 gallon cans at gas station a block away to save about 50cents/gal.... also can get up-to 30 cents/gal tax back for non highway use... so typically pay about $2/gal whereas local AVGAS is about $4.80/ gal. Same station also has non-ethanol REC 90 gas which I use when the plane is not going to fly much as it has longer storage time in plane, it it cost about 40 cents /gal more and engine runs same.

A buddy asked me to recommend a first airplane to buy after getting his private, and said I’d find one that has the MOGAS STC available for above reasons.

does anyone have history with using the MOGAS non-ethanol fuel STC? How difficult is it to find on a typical GA field?

I'm asking about the text I emphasized. does "c172" mean Cessna 172? If so, what STC are you using that allows gasoline with ethanol? What is the ethanol limit?
My understanding is that type certificated planes need an STC to use fuels other than those listed in their type certificate.

What Cessna 172 models come with a "flex-fuel" engine? The STC covers the fuel system as well as the engine.

 

[YooperMooney]

Yes, although it's not necessarily the engine, but the routing of the fuel to the engine. The O-540 can run it certain airframes, but on other airframes vapor lock happens. Even the O-300 will vapor lock when it's 90+ degrees out. Direct injection would/could/should(?) solve the issue, but that's not exactly a legacy engine, and good luck on getting the FAA to allow Lycontinental to build them cheaply to retrofit a couple hundred thousand airframes.

I’m curious what the market will allow 100LL to reach. Would you pay $15/gal?

Meanwhile a large volcano spews out more impurities per minute into the atmosphere than the entire GA fleet probably emits in a decade. When I worked as a firefighter I would ponder how many pollutants are spewed into the air from a house or car fire. Burning all of those plastics and chemicals...
Zero consideration is given to what actually makes a difference; cost vs benefit.

 

[AlphaPilotFlyer]

Yes, c172 = Cessna 172, it has a Corsair V8 conversion that is flex fuel rated.... not original Lycoming. POH supp requires minimum 85 octane as it’s a 500 HP marine engine but flat rated to airframe cert limit so it’s nowhere near it’s related output which allows for the lower octane.....recommended fuel is non-ethanol min 87, usually called Rec 90 (recreational) as it has longer safe storage time in humid environments. The redundant EFI system has O2 sensors and adjust for the different types of fuel automatically, just as your car.

I considered the MOGAS STC for the original engine but it was still a high op cost for old tech. I would recommend any one with the MOGAS STC on legacy engines to look into the highway tax rebate in their state, as any bit helps.

 

[PaulMillner]

it’s reasonable to believe AVGAS will not likely be available as soon as FAA signs off on alternative.

I *think* what you mean is that leaded avgas won't be available as soon as unleaded avgas becomes available.

When [the FAA finds] a supplier, they will have a monopoly and a captive audience.

The FAA isn't seeking a supplier... they don't buy much avgas. What they are doing is offering two separate paths to certification of unleaded avgas for the fleet, PAFI and the STC route. (Remember, Phillips 20W50 was initially introduced via STC.)

But FAA approval isn't the end of the road, there's a bunch of work to do to bring a new fuel to the marketplace.

There are 5 groups/companies working on different formulations: GAMI, Swift, Phillips/Afton, Lyondell/VP-Racing, and Shell Global Solutions (*not* the Shell refining company).

An upcoming Aviation Consumer article details the progress of each of the five contenders. There could well be FAA certification in 2021... that fuel won't be available at your local airport this year, most likely... there's a bunch of steps between certification and mass production. But the Aviation Consumer article is very well written; or, at least it was when I sent it to the editor.

some owners experience premature engine wear and problems they claimed were a direct result of burning non ethanol MOGAS under a STC.

That's possible if fuel octane didn't meet engine requirements.

I have a c172 with a flex fuel rated engine

It would be great to learn more about that! A Cessna 172 running an automotive engine under experimental development, or?

does anyone have history with using the ethanol-free mogas STC? How difficult is it to find on a typical GA field?

There's a bunch of sources that show mogas availability... in general, it is rarely available on airports for a combination of legal and logistical reasons.

Paul

 

[AlphaPilotFlyer]

C172 running under experimental with flex fuel V8. It’s in development for STC but liability in US will likely only have it available outside US or for govt PAO category. The conversion is currently exp exhibition category.

I have not had much problem finding MOGAS at my airports, but AVGAS is also an approved fuel for the EFI system, but you need to do a standard run-up to burn clean plugs whereas not required with MOGAS as long as engine display is normal without annunciated faults.....but your oil change interval goes to just 50 hours. There’s a couple of companies developing auto-conversions, mine is corsairpower.com if you want more info.....there is a section that discusses MOGAS v. AVGAS. I have heard of experimentals finding contaminated MOGAS on airports, mostly due to long storage times in the truck or tanks....but it’s been a while. Clean fuel is a must, and avoid sources with slow moving stock, especially with ethanol. The V8 has 2 additional fuel filers, one for each EFI system, for this reason.

I did mean to say AVGAS will likely be outlawed as soon as FAA signs off on alternate fuel. They’ve been trying to do this since I started flying in the 1980s in California and most either gave up even with grant funding, or left the FAA partnership programs to go it alone..... with GA withering, and small market, I don’t think any supplier gaining approval will be focused on lowering cost.

I removed the anti siphon valve on my airport car and fill the plane using a 12V pump that cost $100 at a farm store, works great and don’t have to worry about AVGAS issue.

 

[Clip4]

There used to be guys who sold the real lead additive in quart bottles or by the case about 12 years ago for antique cars.